Fatores de risco associados à severidade de atropelamentos em áreas urbanas: uma análise categórica temporal

• Ano de defesa: 2021
• Autor(a) principal: Silva, Mateus Nogueira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Severidade dos atropelamentos; Pedestres; Modelos categóricos; Heterogeneidade não observada; Variações temporais
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/59080

The application of measures to ensure the safety and prioritization of pedestrians requires an understanding of the risk factors associated with injuries in crashes. Categorical models are commonly used for this purpose. This research aims to carry out a confirmatory analysis regarding the factors that influence the severity of being run over, considering different aggregations of severity levels, unobserved heterogeneity in the factors and possible temporal variations during the Decade of Action for Road Safety in Fortaleza. For this, it was initially proposed a theoretical model to be confirmed with the aspects that are believed to have an influence on the outcome of the injuries. Categorical models with different levels of severity aggregation were estimated to confirm the theoretical model and analyze the influence of this aggregation on the modeling. In addition, a model of random parameters was estimated to incorporate a possible unobserved heterogeneity. To assess possible changes in risk factors over time, categorical models were also estimated for three periods between the years 2008 and 2019. The results indicated that the combination of some levels of severity can lead to different significant variables and, thus, depending on of specifying the response variable, the influence of important risk factors may end up being ignored in the model. In addition, the model with three severity categories (mild/moderate, severe and fatal) showed the best performance in terms of adjusting the model. Of the factors investigated, only the variable referring to the pedestrian's age over 60 obtained a significant random parameter. The heterogeneity in the observations may be associated in this case, among other factors, with the physical fragility of the body and the cognitive function that may differ between individuals in this group. It was also observed from this model that crashes that occurred at night, with heavy vehicles, on weekends and located on roads with a higher road classification are associated with more serious injuries. Finally, from the temporal analysis, a change in the profile of the severity of crashes involving pedestrians in the city of Fortaleza was evident over these 12 years. Although it is not possible to state that this change comes from specific actions applied to the city, the results presented here indicate an improvement in road safety for these users, in line with the objectives of the Safe Systems Approach and the Decade of Action for Road Safety to reduce serious and fatal traffic injuries.